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Footprints made by two species of ancient human relative were found in Kenya. This one is thought to have been left by Paranthropus boisei.Credit: Kevin G. Hatala
Some 1.5 million years ago, two ancient hominin species crossed paths on a lake shore in Kenya. Their footprints in the mud were frozen in time and lay undiscovered until 2021. Now, analysis of the impressions reveals that they belonged to Homo erectus, a forebear of modern humans, and the more distant relative Paranthropus boisei. The two individuals walked through the lake area within hours or days of each other — leaving the first direct record of different archaic hominin species coexisting in the same place.
Negotiators in Busan, South Korea, were unable to thrash out a United Nations treaty to drastically cut plastic pollution. One fundamental difference blocked agreement: some nations aim to reduce production of non-essential plastics; others, particularly those who make petrochemicals, prefer to focus on waste management. Participants are expected to reconvene next year to try again. In the meantime, some argue that the nearly 100 countries that pushed for a legally binding pledge to reduce production — including the United Kingdom, European Union, African Group and many South American nations — should go ahead and forge their own agreement.
Political deal-making has pressed pause on Norway’s controversial plan to allow seabed mining for valuable minerals. SV, a small environmentalist party, demanded the move in return for its support of the governing party’s budget. The government is also in the midst of a court case brought by the environmental group WWF Norway. Proponents say that deep-sea mining is essential to power the green transition and maintain energy security; opponents say that it could irreversibly damage biodiversity and ecosystems.
Read more: First approval for controversial sea-bed mining worries scientists (Nature | 4 min read, from January)
Features & opinion
For The Impossible Man, the first book-length biography of mathematical physicist Roger Penrose, writer Patchen Barss had extraordinary access to the personal life of the Nobel-prizewinner who helped to establish the theory of black holes. “The book portrays the mathematician as in equal parts hugely influential and endlessly contentious,” writes Nature reporter Davide Castelvecchi in his review. “The book is also a meditation on the human costs of being a person of genius and how others often bear those costs.”
Criminal groups in Mexico are recruiting chemistry students to upgrade their production of the drug fentanyl. Crackdowns on the trade in precursors from China have put the gangs under pressure, and they hope to develop the ability to produce these raw materials in-house. In some cases, students enrol in chemistry classes to gain skills relevant to the illicit trade. “Sometimes when I am teaching them synthesis of pharmaceutical drugs, they openly ask me, ‘Hey, professor, when are you teaching us how to synthesize cocaine and other things?’” says one anonymous chemist.
The New York Times | 10 min read
How do you solve a problem like dark matter? Or explain why the Universe is built the way it is? For physicists, there’s been one answer that has worked for nearly one hundred years: take two particles and smash them together as hard as you can. But the current generation of massive colliders, such as the Large Hadron Collider at CERN, haven’t produced the flood of new particles some scientists were expecting. So attention is turning to a new variant on the collider theme, using particles that have never been smashed together before: muons.
On Friday, Leif Penguinson was hanging out with the thousands of waterfowl at Great River and Clarence Cannon National Wildlife Refuges in Missouri. Did you find the penguin? When you’re ready, here’s the answer.
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Flora Graham, senior editor, Nature Briefing
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